// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use crate::traits::{
	fungible::{Inspect, Mutate},
	tokens::{
		DepositConsequence, Fortitude, Precision, Preservation, Provenance, WithdrawConsequence,
	},
};
use core::fmt::Debug;
use sp_arithmetic::traits::AtLeast8BitUnsigned;
use sp_runtime::traits::{Bounded, Zero};

/// Test [`Mutate::mint_into`] for successful token minting.
///
/// It ensures that account balances and total issuance values are updated correctly after
/// minting tokens into two distinct accounts.
pub fn mint_into_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account_0 = AccountId::from(0);
	let account_1 = AccountId::from(1);

	// Test: Mint an amount into each account
	let amount_0 = T::minimum_balance();
	let amount_1 = T::minimum_balance() + 5.into();
	T::mint_into(&account_0, amount_0).unwrap();
	T::mint_into(&account_1, amount_1).unwrap();

	// Verify: Account balances are updated correctly
	assert_eq!(T::total_balance(&account_0), amount_0);
	assert_eq!(T::total_balance(&account_1), amount_1);
	assert_eq!(T::balance(&account_0), amount_0);
	assert_eq!(T::balance(&account_1), amount_1);

	// Verify: Total issuance is updated correctly
	assert_eq!(T::total_issuance(), initial_total_issuance + amount_0 + amount_1);
	assert_eq!(T::active_issuance(), initial_active_issuance + amount_0 + amount_1);
}

/// Test [`Mutate::mint_into`] for overflow prevention.
///
/// This test ensures that minting tokens beyond the maximum balance value for an account
/// returns an error and does not change the account balance or total issuance values.
pub fn mint_into_overflow<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account = AccountId::from(10);
	let amount = T::Balance::max_value() - 5.into() - initial_total_issuance;

	// Mint just below the maximum balance
	T::mint_into(&account, amount).unwrap();

	// Verify: Minting beyond the maximum balance value returns an Err
	T::mint_into(&account, 10.into()).unwrap_err();

	// Verify: The balance did not change
	assert_eq!(T::total_balance(&account), amount);
	assert_eq!(T::balance(&account), amount);

	// Verify: The total issuance did not change
	assert_eq!(T::total_issuance(), initial_total_issuance + amount);
	assert_eq!(T::active_issuance(), initial_active_issuance + amount);
}

/// Test [`Mutate::mint_into`] for handling balances below the minimum value.
///
/// This test verifies that minting tokens below the minimum balance for an account
/// returns an error and has no impact on the account balance or total issuance values.
pub fn mint_into_below_minimum<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	// Skip if there is no minimum balance
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account = AccountId::from(10);
	let amount = T::minimum_balance() - 1.into();

	// Verify: Minting below the minimum balance returns Err
	T::mint_into(&account, amount).unwrap_err();

	// Verify: noop
	assert_eq!(T::total_balance(&account), T::Balance::zero());
	assert_eq!(T::balance(&account), T::Balance::zero());
	assert_eq!(T::total_issuance(), initial_total_issuance);
	assert_eq!(T::active_issuance(), initial_active_issuance);
}

/// Test [`Mutate::burn_from`] for successfully burning an exact amount of tokens.
///
/// This test checks that burning tokens with [`Precision::Exact`] correctly reduces the account
/// balance and total issuance values by the burned amount.
pub fn burn_from_exact_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Setup account
	let account = AccountId::from(5);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Test: Burn an exact amount from the account
	let amount_to_burn = T::Balance::from(5);
	let preservation = Preservation::Expendable;
	let precision = Precision::Exact;
	let force = Fortitude::Polite;
	T::burn_from(&account, amount_to_burn, preservation, precision, force).unwrap();

	// Verify: The balance and total issuance should be reduced by the burned amount
	assert_eq!(T::balance(&account), initial_balance - amount_to_burn);
	assert_eq!(T::total_balance(&account), initial_balance - amount_to_burn);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance - amount_to_burn);
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance - amount_to_burn);
}

/// Test [`Mutate::burn_from`] for successfully burning tokens with [`Precision::BestEffort`].
///
/// This test verifies that the burning tokens with best-effort precision correctly reduces the
/// account balance and total issuance values by the reducible balance when attempting to burn
/// an amount greater than the reducible balance.
pub fn burn_from_best_effort_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Setup account
	let account = AccountId::from(5);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Get reducible balance
	let force = Fortitude::Polite;
	let reducible_balance = T::reducible_balance(&account, Preservation::Expendable, force);

	// Test: Burn a best effort amount from the account that is greater than the reducible
	// balance
	let amount_to_burn = reducible_balance + 5.into();
	let preservation = Preservation::Expendable;
	let precision = Precision::BestEffort;
	assert!(amount_to_burn > reducible_balance);
	assert!(amount_to_burn > T::balance(&account));
	T::burn_from(&account, amount_to_burn, preservation, precision, force).unwrap();

	// Verify: The balance and total issuance should be reduced by the reducible_balance
	assert_eq!(T::balance(&account), initial_balance - reducible_balance);
	assert_eq!(T::total_balance(&account), initial_balance - reducible_balance);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance - reducible_balance);
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance - reducible_balance);
}

/// Test [`Mutate::burn_from`] handling of insufficient funds when called with
/// [`Precision::Exact`].
///
/// This test verifies that burning an amount greater than the account's balance with exact
/// precision returns an error and does not change the account balance or total issuance values.
pub fn burn_from_exact_insufficient_funds<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	// Set up the initial conditions and parameters for the test
	let account = AccountId::from(5);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Verify: Burn an amount greater than the account's balance with Exact precision returns
	// Err
	let amount_to_burn = initial_balance + 10.into();
	let preservation = Preservation::Expendable;
	let precision = Precision::Exact;
	let force = Fortitude::Polite;
	T::burn_from(&account, amount_to_burn, preservation, precision, force).unwrap_err();

	// Verify: The balance and total issuance should remain unchanged
	assert_eq!(T::balance(&account), initial_balance);
	assert_eq!(T::total_balance(&account), initial_balance);
	assert_eq!(T::total_issuance(), initial_total_issuance);
	assert_eq!(T::active_issuance(), initial_active_issuance);
}

/// Test [`Mutate::restore`] for successful restoration.
///
/// This test verifies that restoring an amount into each account updates their balances and the
/// total issuance values correctly.
pub fn restore_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account_0 = AccountId::from(0);
	let account_1 = AccountId::from(1);

	// Test: Restore an amount into each account
	let amount_0 = T::minimum_balance();
	let amount_1 = T::minimum_balance() + 5.into();
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	T::restore(&account_0, amount_0).unwrap();
	T::restore(&account_1, amount_1).unwrap();

	// Verify: Account balances are updated correctly
	assert_eq!(T::total_balance(&account_0), amount_0);
	assert_eq!(T::total_balance(&account_1), amount_1);
	assert_eq!(T::balance(&account_0), amount_0);
	assert_eq!(T::balance(&account_1), amount_1);

	// Verify: Total issuance is updated correctly
	assert_eq!(T::total_issuance(), initial_total_issuance + amount_0 + amount_1);
	assert_eq!(T::active_issuance(), initial_active_issuance + amount_0 + amount_1);
}

/// Test [`Mutate::restore`] handles balance overflow.
///
/// This test verifies that restoring an amount beyond the maximum balance returns an error and
/// does not change the account balance or total issuance values.
pub fn restore_overflow<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account = AccountId::from(10);
	let amount = T::Balance::max_value() - 5.into() - initial_total_issuance;

	// Restore just below the maximum balance
	T::restore(&account, amount).unwrap();

	// Verify: Restoring beyond the maximum balance returns an Err
	T::restore(&account, 10.into()).unwrap_err();

	// Verify: The balance and total issuance did not change
	assert_eq!(T::total_balance(&account), amount);
	assert_eq!(T::balance(&account), amount);
	assert_eq!(T::total_issuance(), initial_total_issuance + amount);
	assert_eq!(T::active_issuance(), initial_active_issuance + amount);
}

/// Test [`Mutate::restore`] handles restoration below the minimum balance.
///
/// This test verifies that restoring an amount below the minimum balance returns an error and
/// does not change the account balance or total issuance values.
pub fn restore_below_minimum<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	// Skip if there is no minimum balance
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let account = AccountId::from(10);
	let amount = T::minimum_balance() - 1.into();
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Verify: Restoring below the minimum balance returns Err
	T::restore(&account, amount).unwrap_err();

	// Verify: noop
	assert_eq!(T::total_balance(&account), T::Balance::zero());
	assert_eq!(T::balance(&account), T::Balance::zero());
	assert_eq!(T::total_issuance(), initial_total_issuance);
	assert_eq!(T::active_issuance(), initial_active_issuance);
}

/// Test [`Mutate::shelve`] for successful shelving.
///
/// This test verifies that shelving an amount from an account reduces the account balance and
/// total issuance values by the shelved amount.
pub fn shelve_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Setup account
	let account = AccountId::from(5);
	let initial_balance = T::minimum_balance() + 10.into();

	T::restore(&account, initial_balance).unwrap();

	// Test: Shelve an amount from the account
	let amount_to_shelve = T::Balance::from(5);
	T::shelve(&account, amount_to_shelve).unwrap();

	// Verify: The balance and total issuance should be reduced by the shelved amount
	assert_eq!(T::balance(&account), initial_balance - amount_to_shelve);
	assert_eq!(T::total_balance(&account), initial_balance - amount_to_shelve);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance - amount_to_shelve);
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance - amount_to_shelve);
}

/// Test [`Mutate::shelve`] handles insufficient funds correctly.
///
/// This test verifies that attempting to shelve an amount greater than the account's balance
/// returns an error and does not change the account balance or total issuance values.
pub fn shelve_insufficient_funds<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();

	// Set up the initial conditions and parameters for the test
	let account = AccountId::from(5);
	let initial_balance = T::minimum_balance() + 10.into();
	T::restore(&account, initial_balance).unwrap();

	// Verify: Shelving greater than the balance with Exact precision returns Err
	let amount_to_shelve = initial_balance + 10.into();
	T::shelve(&account, amount_to_shelve).unwrap_err();

	// Verify: The balance and total issuance should remain unchanged
	assert_eq!(T::balance(&account), initial_balance);
	assert_eq!(T::total_balance(&account), initial_balance);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance);
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance);
}

/// Test [`Mutate::transfer`] for a successful transfer.
///
/// This test verifies that transferring an amount between two accounts with updates the account
/// balances and maintains correct total issuance and active issuance values.
pub fn transfer_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account_0 = AccountId::from(0);
	let account_1 = AccountId::from(1);
	let initial_balance = T::minimum_balance() + 10.into();
	T::set_balance(&account_0, initial_balance);
	T::set_balance(&account_1, initial_balance);

	// Test: Transfer an amount from account_0 to account_1
	let transfer_amount = T::Balance::from(3);
	T::transfer(&account_0, &account_1, transfer_amount, Preservation::Expendable).unwrap();

	// Verify: Account balances are updated correctly
	assert_eq!(T::total_balance(&account_0), initial_balance - transfer_amount);
	assert_eq!(T::total_balance(&account_1), initial_balance + transfer_amount);
	assert_eq!(T::balance(&account_0), initial_balance - transfer_amount);
	assert_eq!(T::balance(&account_1), initial_balance + transfer_amount);

	// Verify: Total issuance doesn't change
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance * 2.into());
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance * 2.into());
}

/// Test calling [`Mutate::transfer`] with [`Preservation::Expendable`] correctly transfers the
/// entire balance.
///
/// This test verifies that transferring the entire balance from one account to another with
/// when preservation is expendable updates the account balances and maintains the total
/// issuance and active issuance values.
pub fn transfer_expendable_all<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account_0 = AccountId::from(0);
	let account_1 = AccountId::from(1);
	let initial_balance = T::minimum_balance() + 10.into();
	T::set_balance(&account_0, initial_balance);
	T::set_balance(&account_1, initial_balance);

	// Test: Transfer entire balance from account_0 to account_1
	let preservation = Preservation::Expendable;
	let transfer_amount = initial_balance;
	T::transfer(&account_0, &account_1, transfer_amount, preservation).unwrap();

	// Verify: Account balances are updated correctly
	assert_eq!(T::total_balance(&account_0), T::Balance::zero());
	assert_eq!(T::total_balance(&account_1), initial_balance * 2.into());
	assert_eq!(T::balance(&account_0), T::Balance::zero());
	assert_eq!(T::balance(&account_1), initial_balance * 2.into());

	// Verify: Total issuance doesn't change
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance * 2.into());
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance * 2.into());
}

/// Test calling [`Mutate::transfer`] function with [`Preservation::Expendable`] and an amount
/// that results in some dust.
///
/// This test verifies that dust is handled correctly when an account is reaped, with and
/// without a dust trap.
///
/// # Parameters
///
/// - dust_trap: An optional account identifier to which dust will be collected. If `None`, dust is
///   expected to be removed from the total and active issuance.
pub fn transfer_expendable_dust<T, AccountId>(dust_trap: Option<AccountId>)
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let account_0 = AccountId::from(10);
	let account_1 = AccountId::from(20);
	let initial_balance = T::minimum_balance() + 10.into();
	T::set_balance(&account_0, initial_balance);
	T::set_balance(&account_1, initial_balance);

	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let initial_dust_trap_balance = match dust_trap.clone() {
		Some(dust_trap) => T::total_balance(&dust_trap),
		None => T::Balance::zero(),
	};

	// Test: Transfer balance
	let preservation = Preservation::Expendable;
	let transfer_amount = T::Balance::from(11);
	T::transfer(&account_0, &account_1, transfer_amount, preservation).unwrap();

	// Verify: Account balances are updated correctly
	assert_eq!(T::total_balance(&account_0), T::Balance::zero());
	assert_eq!(T::total_balance(&account_1), initial_balance + transfer_amount);
	assert_eq!(T::balance(&account_0), T::Balance::zero());
	assert_eq!(T::balance(&account_1), initial_balance + transfer_amount);

	match dust_trap {
		Some(dust_trap) => {
			// Verify: Total issuance and active issuance don't change
			assert_eq!(T::total_issuance(), initial_total_issuance);
			assert_eq!(T::active_issuance(), initial_active_issuance);
			// Verify: Dust is collected into dust trap
			assert_eq!(
				T::total_balance(&dust_trap),
				initial_dust_trap_balance + T::minimum_balance() - 1.into()
			);
			assert_eq!(
				T::balance(&dust_trap),
				initial_dust_trap_balance + T::minimum_balance() - 1.into()
			);
		},
		None => {
			// Verify: Total issuance and active issuance are reduced by the dust amount
			assert_eq!(
				T::total_issuance(),
				initial_total_issuance - T::minimum_balance() + 1.into()
			);
			assert_eq!(
				T::active_issuance(),
				initial_active_issuance - T::minimum_balance() + 1.into()
			);
		},
	}
}

/// Test [`Mutate::transfer`] with [`Preservation::Protect`] and [`Preservation::Preserve`]
/// transferring the entire balance.
///
/// This test verifies that attempting to transfer the entire balance with returns an error when
/// preservation should not allow it, and the account balances, total issuance, and active
/// issuance values remain unchanged.
pub fn transfer_protect_preserve<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	// This test means nothing if there is no minimum balance
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account_0 = AccountId::from(0);
	let account_1 = AccountId::from(1);
	let initial_balance = T::minimum_balance() + 10.into();
	T::set_balance(&account_0, initial_balance);
	T::set_balance(&account_1, initial_balance);

	// Verify: Transfer Protect entire balance from account_0 to account_1 should Err
	let preservation = Preservation::Protect;
	let transfer_amount = initial_balance;
	T::transfer(&account_0, &account_1, transfer_amount, preservation).unwrap_err();

	// Verify: Noop
	assert_eq!(T::total_balance(&account_0), initial_balance);
	assert_eq!(T::total_balance(&account_1), initial_balance);
	assert_eq!(T::balance(&account_0), initial_balance);
	assert_eq!(T::balance(&account_1), initial_balance);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance * 2.into());
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance * 2.into());

	// Verify: Transfer Preserve entire balance from account_0 to account_1 should Err
	let preservation = Preservation::Preserve;
	T::transfer(&account_0, &account_1, transfer_amount, preservation).unwrap_err();

	// Verify: Noop
	assert_eq!(T::total_balance(&account_0), initial_balance);
	assert_eq!(T::total_balance(&account_1), initial_balance);
	assert_eq!(T::balance(&account_0), initial_balance);
	assert_eq!(T::balance(&account_1), initial_balance);
	assert_eq!(T::total_issuance(), initial_total_issuance + initial_balance * 2.into());
	assert_eq!(T::active_issuance(), initial_active_issuance + initial_balance * 2.into());
}

/// Test [`Mutate::set_balance`] mints balances correctly.
///
/// This test verifies that minting a balance using `set_balance` updates the account balance,
/// total issuance, and active issuance correctly.
pub fn set_balance_mint_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Test: Increase the account balance with set_balance
	let increase_amount: T::Balance = 5.into();
	let new = T::set_balance(&account, initial_balance + increase_amount);

	// Verify: set_balance returned the new balance
	let expected_new = initial_balance + increase_amount;
	assert_eq!(new, expected_new);

	// Verify: Balance and issuance is updated correctly
	assert_eq!(T::total_balance(&account), expected_new);
	assert_eq!(T::balance(&account), expected_new);
	assert_eq!(T::total_issuance(), initial_total_issuance + expected_new);
	assert_eq!(T::active_issuance(), initial_active_issuance + expected_new);
}

/// Test [`Mutate::set_balance`] burns balances correctly.
///
/// This test verifies that burning a balance using `set_balance` updates the account balance,
/// total issuance, and active issuance correctly.
pub fn set_balance_burn_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let initial_total_issuance = T::total_issuance();
	let initial_active_issuance = T::active_issuance();
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Test: Increase the account balance with set_balance
	let burn_amount: T::Balance = 5.into();
	let new = T::set_balance(&account, initial_balance - burn_amount);

	// Verify: set_balance returned the new balance
	let expected_new = initial_balance - burn_amount;
	assert_eq!(new, expected_new);

	// Verify: Balance and issuance is updated correctly
	assert_eq!(T::total_balance(&account), expected_new);
	assert_eq!(T::balance(&account), expected_new);
	assert_eq!(T::total_issuance(), initial_total_issuance + expected_new);
	assert_eq!(T::active_issuance(), initial_active_issuance + expected_new);
}

/// Test [`Inspect::can_deposit`] works correctly returns [`DepositConsequence::Success`]
/// when depositing an amount that should succeed.
pub fn can_deposit_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Test: can_deposit a reasonable amount
	let ret = T::can_deposit(&account, 5.into(), Provenance::Minted);

	// Verify: Returns success
	assert_eq!(ret, DepositConsequence::Success);
}

/// Test [`Inspect::can_deposit`] returns [`DepositConsequence::BelowMinimum`] when depositing
/// below the minimum balance.
pub fn can_deposit_below_minimum<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	// can_deposit always returns Success for amount 0
	if T::minimum_balance() < 2.into() {
		return
	}

	let account = AccountId::from(10);

	// Test: can_deposit below the minimum
	let ret = T::can_deposit(&account, T::minimum_balance() - 1.into(), Provenance::Minted);

	// Verify: Returns success
	assert_eq!(ret, DepositConsequence::BelowMinimum);
}

/// Test [`Inspect::can_deposit`] returns [`DepositConsequence::Overflow`] when
/// depositing an amount that would overflow.
pub fn can_deposit_overflow<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account = AccountId::from(10);

	// Test: Try deposit over the max balance
	let initial_balance = T::Balance::max_value() - 5.into() - T::total_issuance();
	T::mint_into(&account, initial_balance).unwrap();
	let ret = T::can_deposit(&account, 10.into(), Provenance::Minted);

	// Verify: Returns success
	assert_eq!(ret, DepositConsequence::Overflow);
}

/// Test [`Inspect::can_withdraw`] returns [`WithdrawConsequence::Success`] when withdrawing an
/// amount that should succeed.
pub fn can_withdraw_success<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Test: can_withdraw a reasonable amount
	let ret = T::can_withdraw(&account, 5.into());

	// Verify: Returns success
	assert_eq!(ret, WithdrawConsequence::Success);
}

/// Test [`Inspect::can_withdraw`] returns [`WithdrawConsequence::ReducedToZero`] when
/// withdrawing an amount that would reduce the account balance below the minimum balance.
pub fn can_withdraw_reduced_to_zero<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance();
	T::mint_into(&account, initial_balance).unwrap();

	// Verify: can_withdraw below the minimum balance returns ReducedToZero
	let ret = T::can_withdraw(&account, 1.into());
	assert_eq!(ret, WithdrawConsequence::ReducedToZero(T::minimum_balance() - 1.into()));
}

/// Test [`Inspect::can_withdraw`] returns [`WithdrawConsequence::BalanceLow`] when withdrawing
/// an amount that would result in an account balance below the current balance.
pub fn can_withdraw_balance_low<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	if T::minimum_balance() == T::Balance::zero() {
		return
	}

	let account = AccountId::from(10);
	let other_account = AccountId::from(100);
	let initial_balance = T::minimum_balance() + 5.into();
	T::mint_into(&account, initial_balance).unwrap();
	T::mint_into(&other_account, initial_balance * 2.into()).unwrap();

	// Verify: can_withdraw below the account balance returns BalanceLow
	let ret = T::can_withdraw(&account, initial_balance + 1.into());
	assert_eq!(ret, WithdrawConsequence::BalanceLow);
}

/// Test [`Inspect::reducible_balance`] returns the full account balance when called with
/// [`Preservation::Expendable`].
pub fn reducible_balance_expendable<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Verify: reducible_balance returns the full balance
	let ret = T::reducible_balance(&account, Preservation::Expendable, Fortitude::Polite);
	assert_eq!(ret, initial_balance);
}

/// Tests [`Inspect::reducible_balance`] returns [`Inspect::balance`] -
/// [`Inspect::minimum_balance`] when called with either [`Preservation::Protect`] or
/// [`Preservation::Preserve`].
pub fn reducible_balance_protect_preserve<T, AccountId>()
where
	T: Mutate<AccountId>,
	<T as Inspect<AccountId>>::Balance: AtLeast8BitUnsigned + Debug,
	AccountId: AtLeast8BitUnsigned,
{
	let account = AccountId::from(10);
	let initial_balance = T::minimum_balance() + 10.into();
	T::mint_into(&account, initial_balance).unwrap();

	// Verify: reducible_balance returns the full balance - min balance
	let ret = T::reducible_balance(&account, Preservation::Protect, Fortitude::Polite);
	assert_eq!(ret, initial_balance - T::minimum_balance());
	let ret = T::reducible_balance(&account, Preservation::Preserve, Fortitude::Polite);
	assert_eq!(ret, initial_balance - T::minimum_balance());
}
